Moisture detection apparatus and process

ABSTRACT

Embodiments of a water detection apparatus are disclosed that can detect characteristics of food products. The apparatus may include a conveying mechanism configured to move a food product through an aperture in the apparatus, a transmitter coil configured to transmit a signal within the aperture, and a receiver coil configured to receive the signal altered by the food product, and a signal processing unit configured to determine an output value associated with the food product moving through the aperture. The output value can be based, at least in part, on the signal and the altered signal. The output value can corresponds to a characteristic of the food product.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

Any and all applications for which a foreign or domestic priority claimis identified in the Application Data Sheet as filed with the presentapplication are hereby incorporated by reference under 37 CFR 1.57 andmade a part of this specification.

BACKGROUND

When some food products, such as fruit, are harvested, the food productis taken to a packing house with different levels of moisture content,for example, the fruit can be too wet, too dry, or just right forprocessing. The fruit can be sorted so that it can be properly prepared.For example, a fruit, such as a date, can be sorted into differentmoisture grades. It can be beneficial to sort fruit by moisture for bothselling the fruit at the correct moisture level that meets customerspecifications and for determining the amount of hydration ordehydration that the fruit requires during processing. After sorting,the fruit can be hydrated, kept in their current condition, or driedbased on their grade so that the fruit will have substantially the samemoisture and consistency.

SUMMARY OF EMBODIMENTS

The systems, methods, and devices of this disclosure each have severalinnovative aspects, no single one of which is solely responsible for theall of the desirable attributes disclosed herein.

In one embodiment, a water detection apparatus for detecting watercontent in a food product, the apparatus comprising: a conveyingmechanism configured to move at least one food product through anaperture in the apparatus; at least one transmitter coil configured totransmit a signal within the aperture, wherein the at least one foodproduct alters the signal; at least one receiver coil configured toreceive the altered signal; and a signal processing unit configured todetermine at least one output value associated with the at least onefood product moving through the aperture based, at least in part, on thesignal and the altered signal, wherein the at least one output valuecorresponds to water content of the at least one food product.

In another embodiment, a method for detecting characteristics of a foodproduct, the method comprising: conveying at least one food productthrough an aperture in a detection apparatus; transmitting a signal, byat least one transmitter coil, within the aperture; receiving, by atleast one receiver coil, a signal altered by the food product;determining at least one output value associated with the at least onefood product moving through the aperture based, at least in part, on thesignal and the altered signal, wherein the at least one output valuecorresponds to water content of the at least one food product, andprocessing the at least one food product based, at least in part, on theat least one output value.

In another embodiment, An apparatus for detecting characteristics in afood product, the apparatus comprising: a conveying mechanism configuredto move at least one food product through an aperture in the apparatus;at least one transmitter coil configured to transmit a signal within theaperture, wherein the at least one food product alters the signal; atleast one receiver coil configured to receive the altered signal; and asignal processing unit configured to determine at least one output valueassociated with the at least one food product moving through theaperture based, at least in part, on the signal and the altered signal,wherein the at least one output value corresponds to an metal detectioncharacteristic and a water content characteristic of the at least onefood product.

Although certain embodiments and examples are disclosed herein,inventive subject matter extends beyond the examples in the specificallydisclosed embodiments to other alternative embodiments and/or uses, andto modifications and equivalents thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages will becomemore readily appreciated as the same become better understood byreference to the following detailed description, when taken inconjunction with the accompanying drawings, wherein:

FIG. 1 illustrates an embodiment of a moisture detection apparatus.

FIGS. 2A and 2B illustrate embodiments of coil loop detection systems.

FIG. 3 illustrates an embodiment of a flow diagram of an illustrativeprocess for determining water activity levels in food products.

FIG. 4 illustrates an embodiment of a phase angle chart.

FIG. 5 illustrates an embodiment of a moisture detection test stand.

FIG. 6 illustrates an embodiment of a moisture detection system with aconveyor-based feed mechanism.

FIG. 7 illustrates an embodiment of a flow diagram of an illustrativeprocess for determining water activity levels in food products.

DETAILED DESCRIPTION

Fruit (e.g., dates) and/or other food product will sometimes requirepre-hydration to soften the fruit and/or food product if it is too dryor dehydration to dry the fruit and/or food product if it is too wet.Moisture and water activity are measured to determine if a fruit needsto be hydrated or dried. Current methods involve sampling lots andmeasuring the moisture or water activity level (Aw) of the fruit andthen steaming or drying the fruit in a room or chamber.

It can be very difficult to detect wet and dry fruits accurately.Infrared cameras and color cameras can be used to detect the moisturecontent of the fruit. The fruit can then be separated into wet and dryfruit. However, the current technology is not very accurate and thecameras can incorrectly categorize the fruit. In some instances, fruitsmay need to be wet in order for the camera to obtain a clear picture,which may add undesirable moisture to the fruit. Additional water infood products, such as dried fruits, can shorten the shelf life. Forexample, one problem with the current technology is that the visualouter appearance of dates can cause the cameras to incorrectlycategorize the fruits.

FIG. 1 illustrates an embodiment of a water detection apparatus 10. Thewater detection apparatus 10 can have a housing 12 and a plurality ofapertures 14. The food product P, such as a fruit, moves through each ofthe apertures. The product can be any type of food product, such asfruit, vegetable, a health or protein bar, or other food product forwhich a moisture level and/or water activity level of the food productis measured during processing. In one embodiment the product is a date.The product P can move through the apertures 14 on a conveyingmechanism, such as a conveyor belt. The water detection apparatus 10 canoperate using a coil loop detection system 20 (illustrated in FIG. 2).Each aperture 14 can have a separate coil loop detection system 20dedicated to measuring the water activity level of the product movingthrough the aperture 14. The size of the aperture 14 can affect theaccuracy of the measured water activity level (Aw). The size of theaperture 14 can be configured to fit the largest size of the fruit beingmeasured without being too large. In some embodiments, decreasing thesize of the aperture 14, such as the height and width, can increase theaccuracy of the measured water activity level (Aw) for individualfruits. To further increase the accuracy one could presort the fruit bysize such as height and then have different apertures for the differentsizes to get a more accurate read on the individual fruits. In theillustrated embodiment, the water detection apparatus 10 has fourapertures 14. In other embodiments, the apparatus 10 can be configuredto have any number of apertures 14, such as, for example, two, three,eight, or any other number as required. In one embodiment, each aperture14 can be two inches by two inches. Each aperture can have a separateset of coils that can be used to measure the product P moving througheach aperture individually.

FIGS. 2A and 2B illustrate embodiments of the coil loop detection system20. Each aperture 14 of the water detection apparatus 10 can include acoil loop detection system 20. The product P flows through the coils.The coil detection system can include at least one transmit coil 22, atleast one receive coil 24, a transmitter 26, a receiver 28, and adetection and control system 30. The coils can surround the aperture 14.In the embodiment illustrated in FIG. 2A, the coil system 20 includesthree equally spaced coils surrounding the aperture 14, two receivecoils 24 on the outside and a transmit coil 22 in between. In someembodiments, such as in FIG. 2B, more than three coils can be used. Insome embodiments, three pairs of coils, including a plurality transmitcoils 22 and a receive coil 24 at each end. As illustrated, three pairsof oscillator coils can provide higher levels of sensitivity. In someembodiments multiple frequencies can provide higher sensitivitymeasurements. Parallel and series arrangements of coils can also beused. In some embodiments, the water detection apparatus 10 can use atleast one coil to transmit a signal and at least one coil to receive thesignal.

Generally, the coil loop detection system 20 uses at least one transmitcoil 24 that connects to an oscillator circuit (e.g., a RF transmitter)26 to produce a signal, which can create a magnetic field. The receivecoils 22 on opposite ends of the transmit coil(s) 22 can receive thesignal through the receiver 28 (e.g., an RF receiver). The receive coils24 can be spaced apart from the transmit coils 22 such that they canreceive equal amounts of signal. As one example, a receive coil 24 oneither side of a single transmit coil 22 as illustrated in FIG. 2A. Asanother example, three sets of coils are illustrated in FIG. 2B. Thetransmit coils 22 and receive coils 24 can be wound in such a way thattheir signals oppose each other such that the net signal across them canbe zero or substantially zero. When a product P enters the coils, theproduct P can disrupt the signal, such as the magnetic field (or field),around it. As the product passes through the field, it can change thebalance of the receiving coils so that the net signal is no longer zero.A digital signal processor (DSP) in the detection and control system 30can process the signal. The detection system 30 can perform productcompensation, phasing, residual compensation filtering, and cancategorize the fruit based on the received signal.

The detectors are capable of detecting changes in the product bymeasuring two effects: resistive and reactive effects. Electricallyconductive materials and many food products by nature are electricallyconductive. Salt and moisture content combine to produce resistiveeffects. Electrically conductive materials produce reactive effects. Forexample, iron is both electrically conductive and ferro-magnetic. Dryproducts can produce very little or substantially zero product effect,whereas wet products can produce a larger product effect.

The measured magnetic field can change as a product moves through thefield and the detection and control system 30 can derive reactive andresistive components associated with the product. When a product movesthrough the coils the ratio of resistive to reactive components isdisrupted. For example, the detection system 30 can be used to measurethe water activity level (Aw) in fruit by measuring the disruption inthe magnetic field of the coils. By correlating numerical values withwater activity level (Aw), the detection system 30 can measure theinternal water activity level (Aw) of the fruit. The Product effect ofthe product P can disrupt the magnetic field similar to a metal object.The Product effect is based at least in part on the internalcharacteristics of the product that can disrupt the magnetic field ofthe Metal Detector. The Product effect is not limited to the ions of theproduct (e.g., the potassium contents of a date) or the bound or unboundwater molecules. The size of the coils and the size of the aperture 14that the product P moves through can affect the accuracy of thedetermination of a water activity level (Aw). To increase the accuracythe temperature of the product and/or environment can be regulated toobtain more accurate results. Product that is higher in temperature canalso tend disrupt the magnetic field more than product that is at alower temperature. Product that moves faster through the coils candisrupt the magnetic field more than a slower product.

The detection system 30 can go through a learning phase, wherein thedetection system 30 determines values associated with various wateractivity levels of a fruit product P. The system can measure the fieldchanges and can derive reactive and resistive components. In oneembodiment, the detection system 30 can convert the ratio betweenreactive and resistive components to a phase angle. FIG. 4 illustratesan embodiment of a phase angle chart illustrating an example of a phaseangle based on the reactive and resistive components. In the illustratedembodiments, the approximate phase angle measurements correspondgenerally to +130 Metallic (ferrous) contaminants, such as iron; +90Dry, non-conductive products, such as grains and cereals; +65Non-ferrous metallic contaminants, such as copper; +20-30 Metalliccontaminants, such as stainless steel; and 0 Wet, conductive products,such as fresh meats and breads.

Once this angle is determined, the detection system 30 can use thisinformation to categorize the water activity level (Aw) of the fruitproducts P moving through the coils. For example, the detection system30 can identify values associated with high and low water activitylevels of dates. The learned values or ranges of values can be used tocreate thresholds associated with a fruit product P. Thresholds can bedetermined and maintained for resistive and reactive effects and can beused to detect different water activity levels (Aw).

Based on the extrapolated water activity level (Aw), the water detectionapparatus can automatically sort the food product P. The sorting can usethe determined thresholds or ranges of the water activity level (Aw). Insome embodiments, the ranges can be programmed by the machine operator.Different ranges can be determined for each type of food product P.

FIG. 3 illustrates a process for measuring a water activity level in afood product that can be performed by water detection apparatus 10discussed above. Though the process can be applied to many differenttypes of fruits or other food products, the process will be describedwith respect to dates. At block 302, the water activity level thresholdsfor the dates are determined. The system can be used to identify aplurality of grades or groupings of the dates. In one embodiment, thedates can be grades that are wet, dry, and ready for processing. Eachgrade is associated with a numerical range for the determined wateractivity level (Aw). The ranges can be determined using empiricaltesting of the dates. This can also be referred to as the learningstage. After the learning stage is complete, the water detectionapparatus can automatically associate the measurements of the fruit withone of the predetermined ranges.

At block 304, the dates are received for processing. At block 306, thedates are measured using the water detection apparatus. The dates areplaced on a conveyer for sorting by the water detection apparatus 10.The dates can be positioned on the conveyer and moved through anaperture 14 of the water detection apparatus 10. In some embodiments,each date can be measured individually, in other embodiments the datescan measured on average in bulk. The dates may be positioned such thatthey are a determined distance apart in order to facilitate measuringthe dates individually. The dates move through the aperture 14 and thecoil loop detection system 20. The coil loop detection system 20determines a measured value associated with the date.

In some embodiments, the food product (e.g., date) can be measured inbulk or measured quantities. For example, putting one pound of dates ina tub, the system can determine whether the plurality of food productshave undesirable characteristics (e.g., dates that are either too wet ortoo dry). In some embodiments, consumer packs comprising a plurality ofthe food product can be measured and rejected as a single unit. Currentmethods rely on sampling which is not as accurate as measuring everyitem. Being able to measure Aw during a real time sorting operation canimprove the quality and consistency of the packed consumer or bulk item.

At block 308, the system uses the measured value associated with thedate to determine the water activity level (Aw) of the date based on thedetermined thresholds. At block 310, based on the determined wateractivity level (Aw), the dates are categorized for further processingusing a reject system using pressurized air via nozzles timed to knockthe product off a the conveyor belt onto another conveyor belt orbin/basket, or using a manual reject mechanism to throw the or push thedate onto another convey belt or bin/basket. For example, dry dates canbe categorized for further hydration and wet dates can be categorizedfor dehydration. In some embodiments, there can be a plurality of wateractivity levels and multiple sorts that further define thepost-processing category. For example, different levels of hydration ordehydration may be required depending on the water activity level of thedate.

Water Detection Apparatus

FIG. 5 illustrates an embodiment of a water detection apparatus 500. Thewater detection apparatus 500 can include a test cell housing 510, acoil detection system 520, and one or more optical detection systems530. The test cell housing 510 can include a temperature sensor todetermine the ambient temperature within the housing 510. The test cellhousing can include a chamber that is configured to shield the test cellhousing 510 and coil detection system 520 from electrostatic andelectromagnetic interference. In some embodiments, the test cell housingincludes a faraday shield or enclosure. In some embodiments, a distancebetween the chamber and the coil loop detection system 520 can begreater than the width of the aperture of the coil loop detection system520, which can help to reduce interference between the chamber and thecoil loop detection system 520.

In some embodiments, the water detection apparatus 500 can be configuredto be vertically oriented. In a vertical orientation, the chamber can bepositioned in the upper portion of the test cell housing 510. Thechamber can be configured to release the food product. In someembodiments, the test cell housing 510 can have release mechanism, whichcan be mechanically and/or electrically actuated to drop the foodproduct from the chamber of the housing 510. Gravity causes the foodproduct to move from the chamber to the bottom of the housing 510. Thefood product can pass through an aperture in the coil loop detectionsystem 620.

In some embodiments, the water detection apparatus 500 can be configuredto be configured to be horizontally oriented. The food product can beconfigured to move through the aperture on a conveying mechanism, suchas a conveyor belt. The speed at which the conveyor belt moves throughthe aperture can be controlled by an operator of the test chamber. Insome embodiments, the speed of the conveyor is fixed at constant rate.

The water detection apparatus 500 can include one or more opticaldetection systems 530. In some embodiments, the optical detection system530 can be configured to determine the speed of the food product at adefined point within the housing 510. In some embodiments, a pluralityof optical speed detection systems can be used to determine the speed ata plurality of points during travel through the housing 510. In someembodiments, the optical detection system can include a temperaturedetection system. The temperature detection system can be used todetermine the temperature of the food product. In some embodiments, thetemperature detection system can be an infrared thermometer.

In some embodiments, the size of the food product can be determined byan optical detection system 530. The size of the food product may bebased on various measurements, such as height, width, length, volume,mass, and/or other measurement parameters that can be used to determinea size of the food product. In some embodiments, the optical detectionsystem 530 can include one or more optical measurement systemsconfigured to determine measurements associated with the size and shapeof the food product. The optical measurement systems may be configuredto determine width, height, length, area, volume, and/or othermeasurements of the food product. In some embodiments, the opticalmeasurement system can be configured to determine a length of the foodproduct along two or more axes. In some embodiments, a weight sensor maybe used to determine the mass or weight of the food product.

The coil loop detection system 520 can include at least one aperture(not shown). The food product P, such as a fruit, moves through theaperture. The product can be any type of food product, such as fruit,vegetable, or other product for which a water content or water activitylevel of the food product is measured. In one embodiment the product isa date. The product P can move through an aperture in order for the coildetection system to determine the water content or water activity levelof the food product. The coil loop detection system 520 can operate asdescribed above with respect to the coil loop detection system 20(illustrated in FIG. 2). The size of the aperture can affect theaccuracy of the measured water activity level. The size of the aperturecan be configured to fit the largest size food product being measuredwithout being too large. In some embodiments, decreasing the size of theaperture, such as the height and width, can increase the accuracy of themeasured water activity level for individual food products. In someembodiments, the size of the aperture is based on the food product beingtested. For example, a test system for determining a water activitylevel for dates can be smaller than a system for determining wateractivity level for avocados.

In some embodiments, the coil loop detection system 520 can beconfigured to determine the unbound or free water content value of thefood product. In some embodiments, the unbound or free water contentvalue of the food product can be directly related to a water detectionsensitivity (WDS) value of the coil loop detection system 520. When thefood product moved through the aperture, the coil loop detection systemcan determine a WDS value. In some embodiments, the WDS value can be atotal value associated with the product effect of the food product bytaking sample measurements of the food product as it moves through thecoil. In some embodiments, the WDS can be an average value associatedwith the product effect of the food product. In some embodiments, theWDS value can be the peak product effect of the food product. The peakwater content may provide a single value for a food product.

The detection and control system, such as the detection and controlsystem 30 illustrated in FIG. 2A can be configured to determine thewater activity level of the food product. In some embodiments, thecontrol system can be configured to calculate a water content density bydividing the WDS value by a size of the food product. The size of thefood product can be a linear value (for example, a length), an area (forexample, a cross section of the food product), a volume, a mass/weight,or another measurement used for determining the size of the foodproduct. The size of the food product can be determined automaticallyusing one or more sensors, as described herein. In some embodiments, thesize is an approximated size or average size of the food. By measuringand calculating a water content density, the accuracy of thedetermination of the water activity level of food product can beimproved.

In some embodiments, compensation tables and/or algorithms can beimplemented in firmware and/or software of the control system todetermine the water activity level. In some embodiments, thedetermination of the water activity level can include a number offactors, such as, for example, the speed of the food product travellingthrough the aperture of the coil loop detection system 520, thetemperature of the food product, and/or the size of the food product.Such algorithms can be used to determine the product effect by passingsamples of the products of different Aw through the system, and systemcan determine how to correlate the Aw by measuring the product effectcaused by the disruption of the field by the product.

The speed of food sample moving through the detector coils can alter theWDS value. In some embodiments, the WDS value increases with the speedof the food product. The temperature of the food product can affect themeasurement. In some embodiments, the WDS value can have a directcorrelation to the temperature of the food product. For example, the WDSvalue can decrease when the temperature of the food product decreasesand increase when the temperature of the food product increases.

In some embodiments, a water activity level of the food product can bedetermined based, in part, on an analysis of the WDS value, thetemperature, the speed, and the size of the food product. Each foodproduct can have defined correlation tables that can be used tocalculate the water activity level of the specific food product.

An advantage of this method is the speed at which a water activitymeasurement can be conducted. In the above described test system, thewater content of the food product can be obtained within a shorterperiod of time. For example, the water detection apparatus can beconfigured to determine the water content level in less than 30 seconds,less than 20 seconds, less than 10 second, or less than 5 seconds. Usingcurrent methods, such as vapor pressure or an and optical sensor tomeasure water activity level can take up to 10 minutes as the testingapparatus has to wait for the vapor pressure to equalize. This can limitthe number of samples that can be tested.

In some embodiments, the detector and control system can be configuredto determine a ripeness index of a specific food product. For example,some thick-skinned fruits, such as, avocados, bananas, and citrusfruits, can include a ripening correlation table that can determine theripeness index. As a fruit ripens, the WDS value can increase. In anillustrative example, the water content value of an avocado increases asit ripens because the avocado produces ethylene and water as a byproductduring ripening/decay. The water is prevented from escaping by the skinof the avocado, unlike more porous fruits, such as dates, which canallow moisture to evaporate.

Conveyor-Based Water Detection System

FIG. 6 illustrates an embodiment of conveyor-based water detectionsystem 600. In this embodiment, the water detection system 600 includesa coil loop detection system 620. The coil loop detection system canhave a plurality of apertures, such as illustrated in FIG. 1. The foodproduct P, such as a fruit, moves through each of the apertures. Theproduct can be any type of food product, such as fruit, vegetable,health bar or other product for which a moisture level or water activitylevel of the food product is measured during processing. In oneembodiment the product is a date. The product P can move through theapertures on a conveying mechanism, such as a conveyor belt 650. Thecoil loop detection system 620 can operate as described above withrespect to the coil loop detection system 20 (illustrated in FIG. 2).Each aperture can have a separate coil loop detection system dedicatedto measuring the WDS value to obtain the water activity level of theproduct moving through the aperture. The size of the aperture can affectthe accuracy of the measured WDS value to obtain the water activitylevel. The coil loop detection system can have any number of apertures.Each aperture can be referred to as a separate line. The food productcan be indexed on each line such that the coil loop detection system canidentify each food product individually. In some embodiments, the foodproduct may be positioned within a holder on the conveyer belt, witheach hold spaced apart at a defined distance. The speed of the conveyor650 can be provided to the coil loop detection system used to measureWDS or another control system. In some embodiments, the speed of theconveyor can be determined by a shaft encoder 655 that can determine howfast the conveyor is moving the food product through the coil loopdetection system 620.

The system 600 can include one or more temperature sensors 610, such asan IR thermometer. The temperature sensors can be configured to measurethe temperature of individual food products (for example, dates). Insome embodiments, there can be a temperature sensor for each line. Insome embodiments, one temperature sensor can determine temperatures formultiple lines. The temperature information for each food product can beprovided to the coil loop detection system 620.

An electronic measurement sensor 630, such as an optical sensor, can beconfigured to determine a measurement of the food product. For example,in one embodiment, the measurement sensor can determine the length ofthe food product. In some embodiments, a measurement sensor can beprovided for each product line. In some embodiments, the measurementsensor 630 may also be configured to determine the speed of the foodproduct moving along the conveyor. The size (for example, the length) ofeach food product can be provided to the coil loop detection system. Insome embodiments, the measurement sensor can determine the position ofthe food product so the coil loop detection system 620 can determinewhen to sort the food product by blowing it off the conveyor.

The system 600 can include a plurality of pneumatic nozzles 640configured to sort the food product into a plurality of sorting bins660. The pneumatic nozzles 640 can be configured to knock the foodproduct off the conveyor and into the sorting bins 660 using compressedair. In some embodiments, the pneumatic nozzles 660 can use compressedair at 60 to 90 psi. The coil loop detection system can provideinstructions to the pneumatic nozzles in order to sort the food product.The illustrated embodiment includes sorting bins 660A and 660B, however,any number of sorting bins can be used. In some embodiments, the sortingbins 660 may also represent chutes or slides that transport the foodproduct to another processing area or conveyor.

The coil loop detection system can be configured to determine the wateractivity level of each of the food product for use during sorting. Thecoil loop detection system can determine an estimated water activitylevel based, at least in part, on the food product temperature, theconveyor speed, the size of the food product, and the WDS value outputby movement of the food product through the coils. In some embodiments,the coil loop detection system 620 can use additional or fewer factorsto determine the water activity level. The water activity level can becompared to one or more threshold levels. The threshold levels can beused to categorize each of the food products for sorting. For example, afood product, such as dates, may be divided between wet, dry, andproduction ready dates. The dates can be categorized by the coil loopdetection system 620 during runtime operation and automatically sortedinto bins 660 by the pneumatic nozzles 640.

In another embodiment both Metal detection and Water activity and can bemeasured in one device. Generally, the product effect is outside therange used for metal detection and has as smaller peak signal than apiece of metal. The resistance-reactance ratio or phase angle at one ormore frequencies and signal size can be used and interpreted by thesystem to distinguish between a metal object and the water content of aproduct. The system can be configured to have a plurality of rejectionmodes for a specific product, such as, for example, Wet, Dry, and metalrejection modes. The product having the desired characteristics can passthrough without being rejected. The interpretation of the measuredsignal can be used to determine if the product includes undesirablecharacteristics such as metal, or being a wet or dry product. Themeasurement of the signal may be performed using various methods knownin the art. In some embodiments it is desirable to have an Aw of less0.70 to produce a shelf stable product.

FIG. 7 illustrates an embodiment of a flowchart of process fordetermining water activity in a food product. The process 700 can beimplemented by a system configured to control the water activitydetection system. For example, the process 700, in whole or in part, canbe implemented by a detection and control system 30, or other computingsystem configured to control operation of aspects of the water activitydetection system. Although any number of systems, in whole or in part,can implement the process 700, to simplify discussion, the process 700will be described with respect to water activity detection systems.

At block 702, the system determines the size of the product. In someembodiments, the size of the food product can be determined by one ormore sensors or a camera. The size of the food product may be based onvarious measurements, such as height, width, length, volume, mass,and/or other measurement parameters that can be used to determine a sizeof the food product.

At block 704, the system can determine the temperature of the foodproduct. The temperature of the food product can affect the value of themeasurement by the coil loop detection system. In some embodiments, theWDS value can have a direct correlation to the temperature of the foodproduct. For example, the WDS value can decrease with when thetemperature of the food product decreases and increase when thetemperature of the food product increases.

At block 706, the system can determine the speed of the food product.The speed of food sample moving through the detector coils can alter theWDS value. In some embodiments, the WDS value increases with the speedof the food product.

At block 708, the dates are measured using the water detectionapparatus. The food product is moved through an aperture of the waterdetection apparatus. The coil loop detection system determines ameasured WDS value associated with each food product individually.

At block 710, the system uses the measured values associated with thefood product to calculate and extrapolate the water activity level (Aw)of the food product. The coil loop detection system can determine anestimated water activity level based, at least in part, humidity of theatmosphere, on the food product temperature, the food product speed, thesize of the food product, and the WDS value by movement of the foodproduct through the coils. In some embodiments, the coil loop detectionsystem 620 can use additional or fewer factors to determine the wateractivity level. The water activity level can be compared to one or morethreshold levels to categorize the food product.

At block 712, based on the determined water activity level (Aw), thedates are categorized for further processing using a reject system usingpressurized air via nozzles or mechanical movement timed to knock theproduct off a the conveyor belt onto another conveyor belt orbin/basket, or using a manual reject mechanism to throw the or push thedate onto another convey belt or bin/basket. For example, dry dates canbe categorized for further hydration and wet dates can be categorizedfor dehydration. In some embodiments, there can be a plurality of wateractivity levels and multiple sorts that further define thepost-processing category. For example, different levels of hydration ordehydration may be required depending on the water activity level of thedate.

Embodiments have been described in connection with the accompanyingdrawings. However, it should be understood that the foregoingembodiments have been described at a level of detail to allow one ofordinary skill in the art to make and use the devices, systems, etc.described herein. A wide variety of variation is possible. Components,elements, and/or steps may be altered, added, removed, or rearranged.Additionally, processing steps may be added, removed, or reordered.While certain embodiments have been explicitly described, otherembodiments will also be apparent to those of ordinary skill in the artbased on this disclosure.

Some aspects of the systems and methods described herein canadvantageously be implemented using, for example, computer software,hardware, firmware, or any combination of software, hardware, andfirmware. Software can comprise computer executable code for performingthe functions described herein. In some embodiments, computer-executablecode is executed by one or more general purpose computers. However, askilled artisan will appreciate, in light of this disclosure, that anymodule that can be implemented using software to be executed on ageneral purpose computer can also be implemented using a differentcombination of hardware, software, or firmware. For example, such amodule can be implemented completely in hardware using a combination ofintegrated circuits. Alternatively or additionally, such a module can beimplemented completely or partially using specialized computers designedto perform the particular functions described herein rather than bygeneral purpose computers.

While certain embodiments have been explicitly described, otherembodiments will become apparent to those of ordinary skill in the artbased on this disclosure. Therefore, the scope of the invention isintended to be defined by reference to the claims as ultimatelypublished in one or more publications or issued in one or more patentsand not simply with regard to the explicitly described embodiments.

Many other variations than those described herein will be apparent fromthis disclosure. For example, depending on the embodiment, certain acts,events, or functions of any of the algorithms described herein can beperformed in a different sequence, can be added, merged, or left outaltogether (e.g., not all described acts or events are necessary for thepractice of the algorithms). Moreover, in certain embodiments, acts orevents can be performed concurrently, e.g., through multi-threadedprocessing, interrupt processing, or multiple processors or processorcores or on other parallel architectures, rather than sequentially. Inaddition, different tasks or processes can be performed by differentmachines and/or computing systems that can function together.

The various illustrative logical blocks, modules, and algorithm elementsdescribed in connection with the embodiments disclosed herein can beimplemented as electronic hardware, computer software, or combinationsof both. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, and elementshave been described above generally in terms of their functionality.Whether such functionality is implemented as hardware or softwaredepends upon the particular application and design constraints imposedon the overall system. The described functionality can be implemented invarying ways for each particular application, but such implementationdecisions should not be interpreted as causing a departure from thescope of the disclosure.

The various illustrative logical blocks and modules described inconnection with the embodiments disclosed herein can be implemented orperformed by a machine, such as a general purpose processor, a digitalsignal processor (DSP), an application specific integrated circuit(ASIC), a field programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general purpose processor can be a microprocessor,but in the alternative, the processor can be a controller,microcontroller, or state machine, combinations of the same, or thelike. A processor can include electrical circuitry configured to processcomputer-executable instructions. In another embodiment, a processorincludes an FPGA or other programmable device that performs logicoperations without processing computer-executable instructions. Aprocessor can also be implemented as a combination of computing devices,e.g., a combination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration. Although described hereinprimarily with respect to digital technology, a processor may alsoinclude primarily analog components. For example, some or all of thesignal processing algorithms described herein may be implemented inanalog circuitry or mixed analog and digital circuitry. A computingenvironment can include any type of computer system, including, but notlimited to, a computer system based on a microprocessor, a mainframecomputer, a digital signal processor, a portable computing device, adevice controller, or a computational engine within an appliance, toname a few.

The elements of a method, process, or algorithm described in connectionwith the embodiments disclosed herein can be embodied directly inhardware, in a software module stored in one or more memory devices andexecuted by one or more processors, or in a combination of the two. Asoftware module can reside in RAM memory, flash memory, ROM memory,EPROM memory, EEPROM memory, registers, hard disk, a removable disk, aCD-ROM, or any other form of non-transitory computer-readable storagemedium, media, or physical computer storage known in the art. An examplestorage medium can be coupled to the processor such that the processorcan read information from, and write information to, the storage medium.In the alternative, the storage medium can be integral to the processor.The storage medium can be volatile or nonvolatile. The processor and thestorage medium can reside in an ASIC. The ASIC can reside in a userterminal. In the alternative, the processor and the storage medium canreside as discrete components in a user terminal.

Conditional language such as, among others, “can,” “could,” “might” or“may,” unless specifically stated otherwise, are otherwise understoodwithin the context as used in general to convey that certain embodimentsinclude, while other embodiments do not include, certain features,elements and/or steps. Thus, such conditional language is not generallyintended to imply that features, elements and/or steps are in any wayrequired for one or more embodiments or that one or more embodimentsnecessarily include logic for deciding, with or without user input orprompting, whether these features, elements and/or steps are included orare to be performed in any particular embodiment.

Disjunctive language such as the phrase “at least one of X, Y, or Z,”unless specifically stated otherwise, is otherwise understood with thecontext as used in general to present that an item, term, etc., may beeither X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z).Thus, such disjunctive language is not generally intended to, and shouldnot, imply that certain embodiments require at least one of X, at leastone of Y, or at least one of Z to each be present.

Any process descriptions, elements or blocks in the flow diagramsdescribed herein and/or depicted in the attached figures should beunderstood as potentially representing modules, segments, or portions ofcode which include one or more executable instructions for implementingspecific logical functions or elements in the process. Alternateimplementations are included within the scope of the embodimentsdescribed herein in which elements or functions may be deleted, executedout of order from that shown, or discussed, including substantiallyconcurrently or in reverse order, depending on the functionalityinvolved as would be understood by those skilled in the art.

It should be emphasized that many variations and modifications may bemade to the above-described embodiments, the elements of which are to beunderstood as being among other acceptable examples. All suchmodifications and variations are intended to be included herein withinthe scope of this disclosure and protected by the following claims.

What is claimed is:
 1. A water detection apparatus for detecting water content in a food product, the apparatus comprising: a conveying mechanism configured to move at least one food product through an aperture in the apparatus; at least one transmitter coil configured to transmit a signal within the aperture, wherein the at least one food product alters the signal; at least one receiver coil configured to receive the altered signal; and a signal processing unit configured to determine at least one output value associated with the at least one food product moving through the aperture based, at least in part, on the signal and the altered signal, wherein the at least one output value corresponds to water content of the at least one food product.
 2. The apparatus of claim 1, where in the at least one output value of the water content is used to determine a water activity level of the at least one food product.
 3. The apparatus of claim 2, wherein the at least one output value is a numerical value corresponding to the water activity level and is associated with a predetermined range of numerical values.
 4. The apparatus of claim 3, wherein the range of numerical values is predetermined.
 5. The apparatus of claim 1, wherein the apparatus is configured to post-process the at least one food product based on the at least one output value.
 6. The apparatus of claim 5, wherein the post-process associated with the numerical value is hydrating, dehydrating, or doing nothing to the at least one food product.
 7. The apparatus of claim 1, wherein the at least one food product is a fruit.
 8. The apparatus of claim 7, wherein the signal processing component is further configured to determine a ripeness index associated with the fruit.
 9. The apparatus of claim 1, wherein the at least one food product is a date
 10. The apparatus of claim 1, wherein the at least one food product comprises a plurality of food products, and wherein the apparatus is configured to determine the at least one output value associated with the plurality of food products as an individual food product.
 11. The apparatus of claim 1, wherein the height and width of the aperture are sized to be within a defined distance of the food product.
 12. The apparatus of claim 1, wherein the temperature of at least one of the food product or the environment is maintained within a defined temperature range.
 13. The apparatus of claim 1, wherein the determination of the water activity level is based, at least in part, on at least one of humidity, speed, size, or temperature of the food product.
 14. The apparatus of claim 13, wherein signal processing unit is configured to use the water activity level based on a correlation between the at least one output value and at least one of humidity, speed, size, or temperature of the food product.
 15. The apparatus of claim 13, wherein the size includes at least one of length, area, volume, mass, or weight of the food product.
 16. A method for detecting characteristics of a food product, the method comprising: conveying at least one food product through an aperture in a detection apparatus; transmitting a signal, by at least one transmitter coil, within the aperture; receiving, by at least one receiver coil, a signal altered by the food product; determining at least one output value associated with the at least one food product moving through the aperture based, at least in part, on the signal and the altered signal, wherein the at least one output value corresponds to water content of the at least one food product, and processing the at least one food product based, at least in part, on the at least one output value.
 17. The method of claim 16, wherein processing the at least one food product comprises rejecting the at least one food product if the at least one output value is within a defined range of output values.
 18. The method of claim 16 further comprising determining at least one metal detection output value associated with the at least one food product moving through the aperture based, at least in part, on the signal and the altered signal, wherein the at least one metal detection output value corresponds to a metal detection indication of the at least one food product.
 19. The method of claim 1, wherein the at least one food product comprises a plurality of food products, and wherein the at least one output value corresponds to the plurality of food products.
 20. An apparatus for detecting characteristics in a food product, the apparatus comprising: a conveying mechanism configured to move at least one food product through an aperture in the apparatus; at least one transmitter coil configured to transmit a signal within the aperture, wherein the at least one food product alters the signal; at least one receiver coil configured to receive the altered signal; and a signal processing unit configured to determine at least one output value associated with the at least one food product moving through the aperture based, at least in part, on the signal and the altered signal, wherein the at least one output value corresponds to an metal detection characteristic and a water content characteristic of the at least one food product.
 21. The apparatus of claim 20, wherein the apparatus is further configured to determine whether to reject the at least one food product based, at least in part, on at least one of a comparison of the metal detection characteristic to a metal detection criteria or a comparison of the water content characteristic to water content rejection criteria, wherein the metal detection rejection criteria is different that the water content rejection criteria. 